xref: /openbmc/qemu/include/sysemu/replay.h (revision e6b5a071)
1 #ifndef REPLAY_H
2 #define REPLAY_H
3 
4 /*
5  * replay.h
6  *
7  * Copyright (c) 2010-2015 Institute for System Programming
8  *                         of the Russian Academy of Sciences.
9  *
10  * This work is licensed under the terms of the GNU GPL, version 2 or later.
11  * See the COPYING file in the top-level directory.
12  *
13  */
14 
15 #include "qapi/qapi-types-misc.h"
16 #include "qapi/qapi-types-run-state.h"
17 #include "qapi/qapi-types-replay.h"
18 #include "qapi/qapi-types-ui.h"
19 #include "block/aio.h"
20 
21 /* replay clock kinds */
22 enum ReplayClockKind {
23     /* host_clock */
24     REPLAY_CLOCK_HOST,
25     /* virtual_rt_clock */
26     REPLAY_CLOCK_VIRTUAL_RT,
27     REPLAY_CLOCK_COUNT
28 };
29 typedef enum ReplayClockKind ReplayClockKind;
30 
31 /* IDs of the checkpoints */
32 enum ReplayCheckpoint {
33     CHECKPOINT_CLOCK_WARP_START,
34     CHECKPOINT_CLOCK_WARP_ACCOUNT,
35     CHECKPOINT_RESET_REQUESTED,
36     CHECKPOINT_SUSPEND_REQUESTED,
37     CHECKPOINT_CLOCK_VIRTUAL,
38     CHECKPOINT_CLOCK_HOST,
39     CHECKPOINT_CLOCK_VIRTUAL_RT,
40     CHECKPOINT_INIT,
41     CHECKPOINT_RESET,
42     CHECKPOINT_COUNT
43 };
44 typedef enum ReplayCheckpoint ReplayCheckpoint;
45 
46 typedef struct ReplayNetState ReplayNetState;
47 
48 extern ReplayMode replay_mode;
49 
50 /* Name of the initial VM snapshot */
51 extern char *replay_snapshot;
52 
53 /* Replay locking
54  *
55  * The locks are needed to protect the shared structures and log file
56  * when doing record/replay. They also are the main sync-point between
57  * the main-loop thread and the vCPU thread. This was a role
58  * previously filled by the BQL which has been busy trying to reduce
59  * its impact across the code. This ensures blocks of events stay
60  * sequential and reproducible.
61  */
62 
63 void replay_mutex_lock(void);
64 void replay_mutex_unlock(void);
65 
66 /* Replay process control functions */
67 
68 /*! Enables recording or saving event log with specified parameters */
69 void replay_configure(struct QemuOpts *opts);
70 /*! Initializes timers used for snapshotting and enables events recording */
71 void replay_start(void);
72 /*! Closes replay log file and frees other resources. */
73 void replay_finish(void);
74 /*! Adds replay blocker with the specified error description */
75 void replay_add_blocker(Error *reason);
76 /* Returns name of the replay log file */
77 const char *replay_get_filename(void);
78 /*
79  * Start making one step in backward direction.
80  * Used by gdbstub for backwards debugging.
81  * Returns true on success.
82  */
83 bool replay_reverse_step(void);
84 /*
85  * Start searching the last breakpoint/watchpoint.
86  * Used by gdbstub for backwards debugging.
87  * Returns true if the process successfully started.
88  */
89 bool replay_reverse_continue(void);
90 /*
91  * Returns true if replay module is processing
92  * reverse_continue or reverse_step request
93  */
94 bool replay_running_debug(void);
95 /* Called in reverse debugging mode to collect breakpoint information */
96 void replay_breakpoint(void);
97 /* Called when gdb is attached to gdbstub */
98 void replay_gdb_attached(void);
99 
100 /* Processing the instructions */
101 
102 /*! Returns number of executed instructions. */
103 uint64_t replay_get_current_icount(void);
104 /*! Returns number of instructions to execute in replay mode. */
105 int replay_get_instructions(void);
106 /*! Updates instructions counter in replay mode. */
107 void replay_account_executed_instructions(void);
108 
109 /* Interrupts and exceptions */
110 
111 /*! Called by exception handler to write or read
112     exception processing events. */
113 bool replay_exception(void);
114 /*! Used to determine that exception is pending.
115     Does not proceed to the next event in the log. */
116 bool replay_has_exception(void);
117 /*! Called by interrupt handlers to write or read
118     interrupt processing events.
119     \return true if interrupt should be processed */
120 bool replay_interrupt(void);
121 /*! Tries to read interrupt event from the file.
122     Returns true, when interrupt request is pending */
123 bool replay_has_interrupt(void);
124 
125 /* Processing clocks and other time sources */
126 
127 /*! Save the specified clock */
128 int64_t replay_save_clock(ReplayClockKind kind, int64_t clock,
129                           int64_t raw_icount);
130 /*! Read the specified clock from the log or return cached data */
131 int64_t replay_read_clock(ReplayClockKind kind);
132 /*! Saves or reads the clock depending on the current replay mode. */
133 #define REPLAY_CLOCK(clock, value)                                      \
134     (replay_mode == REPLAY_MODE_PLAY ? replay_read_clock((clock))       \
135         : replay_mode == REPLAY_MODE_RECORD                             \
136             ? replay_save_clock((clock), (value), icount_get_raw()) \
137         : (value))
138 #define REPLAY_CLOCK_LOCKED(clock, value)                               \
139     (replay_mode == REPLAY_MODE_PLAY ? replay_read_clock((clock))       \
140         : replay_mode == REPLAY_MODE_RECORD                             \
141             ? replay_save_clock((clock), (value), icount_get_raw_locked()) \
142         : (value))
143 
144 /* Processing data from random generators */
145 
146 /* Saves the values from the random number generator */
147 void replay_save_random(int ret, void *buf, size_t len);
148 /* Loads the saved values for the random number generator */
149 int replay_read_random(void *buf, size_t len);
150 
151 /* Events */
152 
153 /*! Called when qemu shutdown is requested. */
154 void replay_shutdown_request(ShutdownCause cause);
155 /*! Should be called at check points in the execution.
156     These check points are skipped, if they were not met.
157     Saves checkpoint in the SAVE mode and validates in the PLAY mode.
158     Returns 0 in PLAY mode if checkpoint was not found.
159     Returns 1 in all other cases. */
160 bool replay_checkpoint(ReplayCheckpoint checkpoint);
161 /*! Used to determine that checkpoint is pending.
162     Does not proceed to the next event in the log. */
163 bool replay_has_checkpoint(void);
164 
165 /* Asynchronous events queue */
166 
167 /*! Disables storing events in the queue */
168 void replay_disable_events(void);
169 /*! Enables storing events in the queue */
170 void replay_enable_events(void);
171 /*! Returns true when saving events is enabled */
172 bool replay_events_enabled(void);
173 /* Flushes events queue */
174 void replay_flush_events(void);
175 /*! Adds bottom half event to the queue */
176 void replay_bh_schedule_event(QEMUBH *bh);
177 /* Adds oneshot bottom half event to the queue */
178 void replay_bh_schedule_oneshot_event(AioContext *ctx,
179     QEMUBHFunc *cb, void *opaque);
180 /*! Adds input event to the queue */
181 void replay_input_event(QemuConsole *src, InputEvent *evt);
182 /*! Adds input sync event to the queue */
183 void replay_input_sync_event(void);
184 /*! Adds block layer event to the queue */
185 void replay_block_event(QEMUBH *bh, uint64_t id);
186 /*! Returns ID for the next block event */
187 uint64_t blkreplay_next_id(void);
188 
189 /* Character device */
190 
191 /*! Registers char driver to save it's events */
192 void replay_register_char_driver(struct Chardev *chr);
193 /*! Saves write to char device event to the log */
194 void replay_chr_be_write(struct Chardev *s, uint8_t *buf, int len);
195 /*! Writes char write return value to the replay log. */
196 void replay_char_write_event_save(int res, int offset);
197 /*! Reads char write return value from the replay log. */
198 void replay_char_write_event_load(int *res, int *offset);
199 /*! Reads information about read_all character event. */
200 int replay_char_read_all_load(uint8_t *buf);
201 /*! Writes character read_all error code into the replay log. */
202 void replay_char_read_all_save_error(int res);
203 /*! Writes character read_all execution result into the replay log. */
204 void replay_char_read_all_save_buf(uint8_t *buf, int offset);
205 
206 /* Network */
207 
208 /*! Registers replay network filter attached to some backend. */
209 ReplayNetState *replay_register_net(NetFilterState *nfs);
210 /*! Unregisters replay network filter. */
211 void replay_unregister_net(ReplayNetState *rns);
212 /*! Called to write network packet to the replay log. */
213 void replay_net_packet_event(ReplayNetState *rns, unsigned flags,
214                              const struct iovec *iov, int iovcnt);
215 
216 /* Audio */
217 
218 /*! Saves/restores number of played samples of audio out operation. */
219 void replay_audio_out(size_t *played);
220 /*! Saves/restores recorded samples of audio in operation. */
221 void replay_audio_in(size_t *recorded, void *samples, size_t *wpos, size_t size);
222 
223 /* VM state operations */
224 
225 /*! Called at the start of execution.
226     Loads or saves initial vmstate depending on execution mode. */
227 void replay_vmstate_init(void);
228 /*! Called to ensure that replay state is consistent and VM snapshot
229     can be created */
230 bool replay_can_snapshot(void);
231 
232 #endif
233